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quick random row selection in Postgres
... myid FROM mytable OFFSET floor(random()*N) LIMIT 1;
Consider a table of 2 rows; random()*N generates 0 <= x < 2 and for example SELECT myid FROM mytable OFFSET 1.7 LIMIT 1; returns 0 rows because of implicit rounding to nearest int.
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Debugging in Clojure? [closed]
...selected functions.
(use 'clojure.contrib.trace)
(defn fib[n] (if (< n 2) n (+ (fib (- n 1)) (fib (- n 2)))))
(dotrace [fib] (fib 3))
produces the output:
TRACE t4425: (fib 3)
TRACE t4426: | (fib 2)
TRACE t4427: | | (fib 1)
TRACE t4427: | | => 1
TRACE t4428: | | (fib 0...
What is the proper way to format a multi-line dict in Python?
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242
I use #3. Same for long lists, tuples, etc. It doesn't require adding any extra spaces beyond ...
Multiply TimeSpan in .NET
...= TimeSpan.FromMinutes(1);
duration = TimeSpan.FromTicks(duration.Ticks * 12);
Console.WriteLine(duration);
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Putting an if-elif-else statement on one line?
...t's less readable:
>>> i=100
>>> a = 1 if i<100 else 2 if i>100 else 0
>>> a
0
>>> i=101
>>> a = 1 if i<100 else 2 if i>100 else 0
>>> a
2
>>> i=99
>>> a = 1 if i<100 else 2 if i>100 else 0
>>> a
1
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WCF chokes on properties with no “set ”. Any workaround?
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edited Feb 24 '10 at 2:45
answered Feb 24 '10 at 2:34
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Integer division with remainder in JavaScript?
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edited Feb 21 '17 at 8:50
bluish
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In PHP, what is a closure and why does it use the “use” identifier?
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answered Jun 30 '09 at 18:24
Andrew HareAndrew Hare
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How do I raise the same Exception with a custom message in Python?
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12 Answers
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Adjusting the Xcode iPhone simulator scale and size [duplicate]
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210
You can't have 1:1 ratio.
However you can scale it from the iOS Simulator > Window > Sca...